This invention relates to a motorcycle having balloon tires and more particularly to an improved suspension and drive arrangement for an off the road motorcycle.
Off the road vehicles are becoming extremely popular. Such vehicles employ large balloon tires of the low pressure type that permit them to travel over a wide variety of terrains. The application of such wheels and tires has been made to motorcycles as well as three and four wheel vehicles. With a motorcycle, there are certain advantages to providing an additional suspension system in addition to the balloon tire. However, because the tire is normally wider than the width of the frame of the motorcycle, it is difficult to provide an effective suspension system that is capable of sustaining the loads encountered in off the road use.
It is, therefore, a principal object of this invention to provide an improved suspension system for motorcycles having balloon tires.
It is a yet further object of this invention to provide a suspension system for a motorcycle having balloon tires that permits a high degree of force absorption.
Because of the large width of the balloon tire, the driving of the rear wheel of a motorcycle equipped with such tires presents certain problems. That is, the driving chain for the rear wheel will be positioned transversely outwardly of the frame and thus the chain may be exposed in an area where it could be damaged. Furthermore, if the chain extends all the way forward to the engine, it will be in a position where it might interfere with the rider's legs. Therefore, it has been proposed to employ a dual chain system for driving the rear wheels of motorcycles embodying balloon tires. A first chain extends from the engine to an intermediate shaft that is mounted directly in front of the rear wheel. The intermediate shaft, in turn, drives the rear wheel through a second chain that is spaced transversely outwardly from the frame whereas the first chain is positioned inwardly of the frame. However, due to the high driving loads that the first chain encounters and its inward placement, there is a danger that it could become damaged due to overheating.
It is, therefore, a further object of this invention to provide an improved drive arrangement for motorcycles embodying balloon tires.
It is a yet further object of this invention to provide a driving chain arrangement for vehicles wherein the chain is protected by an encompassing member and wherein an arrangement is provided for cooling the chain so as to prevent damage from overheating.